#include <stdio.h>
void main()
{int n,x;
float sum;
scanf("%d",&n);
sum=0.0,x=1;
while((0<=x)&&(x<=n))
{sum=sum+1.0/x;
x++;}
printf("%f",sum);
}
#include <stdio.h>
void main()
{int n,x;
float sum;
scanf("%d",&n);
sum=0.0,x=1;
while((0<=x)&&(x<=n))
{sum=sum+1.0/x;
x++;}
printf("%f",sum);
}